using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Business.Core.Utilities
{
    public class DynamicOrderComparer<T> : IComparer<T>
    {
        private readonly string[] _sortColumns;
        private readonly List<bool> _sortDirections; // true for ascending, false for descending

        public DynamicOrderComparer(string[] sortColumns, bool[] sortDirections)
        {
            _sortColumns = sortColumns;
            _sortDirections = sortDirections.ToList();
        }

        public int Compare(T x, T y)
        {
            for (int i = 0; i < _sortColumns.Length; i++)
            {
                var property = typeof(T).GetProperty(_sortColumns[i]);
                if (property == null) throw new ArgumentException($"Property {_sortColumns[i]} not found in type {typeof(T)}");
                var xValue = property.GetValue(x);
                var yValue = property.GetValue(y);

                if (xValue == null && yValue == null) return 0;
                if (xValue == null) return _sortDirections[i] ? -1 : 1;
                if (yValue == null) return _sortDirections[i] ? 1 : -1;

                var comparison = Comparer<object>.Default.Compare(xValue, yValue);
                if (comparison != 0) return _sortDirections[i] ? comparison : -comparison;
            }
            return 0;
        }
    }
}